1. Field of the Invention
The present invention relates to a method for manufacturing a bump of a probe card, and more particularly to a method for manufacturing a bump of a probe card having a high aspect ratio, a high elasticity, a high durability suitable for testing a high speed device by using a sacrificial substrate as a mold.
2. Description of the Related Art
Generally, a probe card is used for a wafer-level test. A plurality of cantilever structures having a bump, a cantilever beam and a probe tip are formed on the probe card. The cantilever beam which is a main body of the cantilever structure provides an elasticity and the probe tip contacts a pad on a wafer. The bump provides a support for the cantilever beam to allow the probe tip to contact the pad elastically.
An integration density of a semiconductor device increases, a density of the cantilever structure is also increased. In order to test various devices, bumps having various heights are required. While the bump having a high aspect ratio allows attaching a chip capacitor close to the bump, it is difficult to form the bump having the high aspect ratio.
In order to overcome this problem, the applicant filed Korean Patent Application No. 10-2006-0079873 titled “METHOD FOR MANUFACTURING BUMP OF PROBE CARD” disclosing a method for forming a bump having the high aspect ratio using a silicon substrate a mold.
One factor for deciding a durability of the probe card is the elasticity of the cantilever structure. The elasticity of the cantilever structure is determined by the elasticity of the probe beam and the bump. Increasing the elasticity of the bump is very difficult, and particularly, forming a bump that satisfies the elasticity and a stiffness is more difficult.